2012 MERCEDES-BENZ GL-Class low oil pressure

Problems with the transmissionProblemPossible causes/consequences and M SolutionsThe transmission has
problems shifting gear.The transmission is losing oil.XHave the transmission checked at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz Center,
immediately.The acceleration ability
is deteriorating.
The transmission no
longer changes gear.The transmission is in emergency mode.
It is only possible to shift into second gear and reverse gear.XStop the vehicle.XShift the transmission to position P.XSwitch off the engine.XWait at least 10 seconds before restarting the engine.XShift the transmission to position D or R.
If D is selected, the transmission shifts into second gear; if R is
selected, the transmission shifts into reverse gear.XHave the transmission checked at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz Center,
immediately.Transfer case
The vehicle has permanent 4-wheel drive
(4MATIC). Power is always transmitted to
both axles.
! Performance tests may only be carried
out on a 2-axle dynamometer. The brake
system or transfer case could otherwise be
damaged. Contact a qualified specialist
workshop for a performance test.
Mercedes-Benz recommends that you use
an authorized Mercedes-Benz Center for
this purpose.
! If the parking brake is being tested on a
brake dynamometer, the ignition must be
switched off (SmartKey or Start/Stop
button in position 0 or 1), as ESP ®
will
otherwise automatically intervene. The test
must last a maximum of 10 seconds. The
brake system could otherwise be damaged.Refueling
Important safety notes
GWARNING
Gasoline and diesel fuels are highly flammable
and poisonous. They burn violently and can
cause serious injury.
Never allow sparks, flames or smoking
materials near gasoline or diesel fuel!
Turn off the engine before refueling.
Whenever you are around gasoline or diesel
fuel, avoid inhaling fumes and any skin or
clothing contact. Extinguish all smoking
materials.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging your
health.
GWARNING
Overfilling of the fuel tank may create
pressure in the system which could cause a
gas discharge. This could cause the gasoline
Refueling159Driving and parkingZ

damage to the engine or the catalytic
converter. Have excess oil siphoned off.
For further information on engine oil, see
( Y page 375).XReplace cap : on the filler neck and
tighten clockwise.
Ensure that the cap locks into place
securely.
Checking and adding other service
products
Checking the coolant level
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down.
XTurn the SmartKey to position
2 (Y page 149) in the ignition lock.
On vehicles with KEYLESS-GO, press the
Start/Stop button twice ( Y page 149).XCheck the coolant temperature gauge in
the multifunction display.
The coolant temperature must be below
158 ‡ (70 †).GWARNING
In order to avoid any potentially serious burns:
R use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system, or
if the coolant temperature display indicates
that the coolant is overheated.
R do not remove the pressure cap on the
coolant reservoir if the coolant temperature
is above 158 ‡ (70 †). Allow the engine to
cool down before removing the cap. The
coolant reservoir contains hot fluid and is
under pressure.
R using a rag, slowly turn the cap
approximately 1
/ 2 turn to relieve excess
pressure. If opened immediately, scalding
hot fluid and steam will be blown out under
pressure.
R do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts.XSlowly turn cap : half a turn counter-
clockwise and allow excess pressure to
escape.XTurn cap : further counter-clockwise and
remove it.
If the coolant is at the level of marker bar
= in the filler neck when cold, there is
enough coolant in coolant expansion
tank ;.
If the coolant is approximately 0.6 in
(1.5 cm) above marker bar = in the filler
neck when warm, there is enough coolant
in coolant expansion tank ;.XIf necessary, add coolant that has been
tested and approved by Mercedes-Benz.XReplace cap : and turn it clockwise as far
as it will go.
For further information on coolant, see
( Y page 376).
Windshield washer system and
headlamp cleaning system
The washer fluid reservoir is used for both the
windshield washer system and the headlamp
cleaning system.
i Vehicle components and their service
products must match. You should,
Engine compartment303Maintenance and careZ

XClean sensors : of the driving systems
with water, car shampoo and a soft cloth.
! When cleaning the sensors with a power
washer, maintain a distance between the
vehicle and the nozzle of the power washer
of at least 11.8 in (30 cm). Information
about the correct distance is available from
the equipment manufacturer.
Cleaning the rear view camera
XUse clear water and a soft cloth to clean
camera lens :.
!
Do not clean the camera lens and the area
around the rear view camera with a power
washer.
Cleaning the exhaust tail pipes
Impurities combined with the effects of road
grit and corrosive environmental factors may
cause flash rust to form on the surface. You
can restore the original shine of the exhaust
tail pipe by cleaning it regularly, especially in
winter and after washing.
! Do not clean the exhaust tail pipes with
alkaline-based cleaning agents, such as
wheel cleaner.
XClean the exhaust tail pipes with a chrome
care product tested and approved by
Mercedes-Benz.Interior care
Cleaning the displayXBefore cleaning the display, make sure that
it is switched off and has cooled down.XClean the display surface using a
commercially-available microfiber cloth
and TFT/LCD display cleaner.XDry the display surface using a dry
microfiber cloth.
! For cleaning, do not use any of the
following:
R alcohol-based thinner or gasoline
R abrasive cleaning agents
R commercially-available household
cleaning agents
These may damage the display surface. Do
not put pressure on the display surface
when cleaning. This could lead to
irreparable damage to the display.
Cleaning the plastic trim
GWARNING
When cleaning the steering wheel boss and
dashboard, do not use cockpit sprays or
cleaning agents containing solvents. Cleaning
agents containing solvents cause the surface
to become porous, and as a result, plastic
parts may break away and be thrown around
the interior when an air bag is deployed, which
may result in severe injuries.
! Do not affix the following to plastic
surfaces:
R stickers
R films
R scented oil bottles or similar items
You can otherwise damage the plastic.
! Do not allow cosmetics, insect repellent
or sunscreen to come into contact with the
plastic trim. This maintains the high-quality
look of the surfaces.
310CareMaintenance and care

Storing wheels
Store wheels that are not being used in a cool,
dry and preferably dark place. Protect the
tires from oil, grease, gasoline and diesel.
Cleaning the wheels
GWARNING
Do not use power washers with circular-jet
nozzles (dirt grinders) to clean your vehicle, in
particular the tires. You could otherwise
damage the tires and cause an accident.
Wheel and tire combinations
Please bear the following in mind
! For safety reasons, Mercedes-Benz
recommends that you only use Tires and
wheels which have been approved by
Mercedes-Benz specifically for your
vehicle.
These tires have been specially adapted for
use with the control systems, such as ABS
or ESP ®
, and are marked as follows:
R MO = Mercedes-Benz Original
R MOE = Mercedes-Benz Original Extended
(tires featuring run-flat characteristics)
R MO1 = Mercedes-Benz Original (only
certain AMG tires)
Mercedes-Benz Original Extended tires
may only be used on wheels that have been
specifically approved by Mercedes-Benz.
Only use tires, wheels or accessories
tested and approved by Mercedes-Benz.
Certain characteristics, e.g. handling,
vehicle noise emissions or fuel
consumption, may otherwise be adversely
affected. In addition, when driving with a
load, tire dimension variations could cause
the tires to come into contact with the
bodywork and axle components. This could
result in damage to the tires or the vehicle.
Mercedes-Benz accepts no liability for
damage resulting from the use of tires,
wheels or accessories other than those
tested and approved.
Further information about tires, wheels and
approved combinations can be obtained
from any authorized Mercedes-Benz
Center.
i The Tire and Load Information placard
with the recommended tire pressures is
attached to the B-pillar on the driver's side.
Further information about driving at high
speeds or driving with vehicle loads that are
lighter than the maximum vehicle load can
be found in the tire pressure table on the
inside of the fuel filler flap. Check tire
pressures regularly, and only when the tires
are cold. Comply with the maintenance
recommendations of the tire manufacturer
in the vehicle document wallet.
For further information on the recommended
tire inflation pressure and on tire pressures
for specific driving conditions, see
( Y page 341).
i Notes on the vehicle equipment – always
equip the vehicle:
R with tires of the same size on a given axle
(left/right)
R with the same type of tires at a given time
(summer tires, winter tires, MOExtended
tires)
i Vehicles equipped with MOExtended tires
are not equipped with a TIREFIT kit at the
factory. It is therefore recommended that
you additionally equip your vehicle with a
TIREFIT kit if you mount tires that do not
feature run-flat properties, e.g. winter tires.
A TIREFIT kit can be obtained from an
authorized Mercedes-Benz Center.
i On the following pages, you can find
information on approved wheel rims and
tire sizes for equipping your vehicle with
winter tires. Winter tires are not available
from the factory as standard equipment or
optional extras.Wheel and tire combinations363Wheels and tiresZ

Motor Octane Number (MON): (RON +
MON) / 2, also known as knock resistance.
Reformulated Gasoline (RFG) and/or
unleaded gasoline with additives can be used
if the concentration of the additives in the fuel
does not exceed 10%, e.g.:
R Ethanol
R TAME
R ETBE
R IPA
R TBA
For MTBE, the concentration should not
exceed 15%.
The concentration of methanol in gasoline
including other additives must not exceed 3%.
Using mixtures of methanol and ethanol is not
permitted. Gasohol, a mixture of 10% ethanol
and 90% unleaded gasoline, can be used.
All of these mix fuels must fulfill the fuel
requirements, e.g.:
R knock resistance
R boiling point
R vapor pressure
Diesel engines – Important safety notes
! Only use commercially available ULTRA-
LOW SULFUR DIESEL FUEL (ULSD, 15 ppm
MAXIMUM SULFUR) that meets the
ASTM D975 standard. Failure to use
ULTRA-LOW SULFUR DIESEL FUEL (ULSD)
can severely damage the vehicle's exhaust
gas aftertreatment system.
! Do not fill the tank with gasoline. Do not
blend diesel fuel with gasoline or kerosene.
Otherwise, the fuel system and the engine
could be damaged.
To prevent malfunctions, diesel fuel with
improved flow characteristics is available in
the winter months. Check with your gas
station.
Information on the fuel grade can usually be
found on the gas pump. If the information
cannot be found on the gas pump, ask the gas
station personnel. For further information,consult an authorized Mercedes-Benz Center
or go to the Internet site
http://www.mbusa.com (USA only).
Diesel engines – Fuels containing
biodiesel (FAME [fatty acid methyl ester])
Mercedes-Benz USA approves the use of B5
(ULSD with a maximum of up to five percent
by volume biodiesel) for all diesel engines
with common rail direct injection (CDI) and
BlueTEC.
Pure biodiesel and diesel fuels that have a
higher percentage of biodiesel, e.g. B20, can
damage the fuel system and the engine and
are therefore not approved.
For further information, please ask the gas
station personnel. The label on the gas pump
must indicate clearly that the B5 biodiesel
blend fulfills the ULSD standard. If the label
is not clear, do not refuel the vehicle.
Do not refuel your vehicle with fuels unless
they have been approved by Mercedes-Benz.
Additives in gasoline
One of the major problems with poor quality
fuels is the creation of carbon deposits during
the combustion process. Mercedes-Benz
recommends that you use fuel brands
containing additives that prevent the build-up
of carbon deposits.
If you use fuels without these additives for an
extended period of time, there may be a build
up of carbon deposits, especially on the inlet
valves and in the combustion chamber.
This could lead to engine running problems,
e.g.:
R longer engine warm-up phase
R uneven idle
R engine noise
R misfiring
R loss of power
In areas where the availability of gasoline with
relevant additives is not adequate, carbon
deposits can form. In this case, Mercedes-
Benz recommends the use of additives that
Service products and capacities373Technical dataZ